#include <iostream>
#include <opencv2/opencv.hpp>
#include <opencv2/highgui/highgui.hpp>

using namespace std;
using namespace cv;

///Prototype Fungsi
int getMax(int a,int b,int c)
{
    if(a>=b) {
        if(a>=c) return a;
        else return c;
    }
    else{
        if(b>=c) return b;
        else return c;
    }
}
int getMin(int a,int b,int c)
{
    if(a<=b) {
        if(a<=c) return a;
        else return c;
    }
    else{
        if(b<=c) return b;
        else return c;
    }
}
int main()
{
    Mat img = imread("dian_sastro.jpg", CV_LOAD_IMAGE_COLOR);
    //Mat imgHSV = cvCreateMat(img->height, img->width, CV_8UC3);
    //Mat imgHSV2 = cvCreateMat(img->height, img->width, CV_8UC3);
    Mat imgHSV = img.clone();
    Mat imgHSV2 = img.clone();

    // Konversi RGB ke HSV tanpa menggunakan library opencv

    Vec3b oldPixel;
    Vec3b newPixel;
    int b,g,r;
    double h,s,v;
    for(int i=0;i<img.rows;i++)
    {
        for(int j=0;j<img.cols;j++)
        {
            oldPixel = img.at<Vec3b>(i,j);

            // untuk akses pixel
            b=oldPixel.val[0];
            g=oldPixel.val[1];
            r=oldPixel.val[2];
            v=getMax(b,g,r); //[1

            //if
            if(v!=0)
            {
                s=(v-getMin(b,g,r))/v;
            }
            else {
                s=0;
            }

            if(s==0) h=0;
            else
            {
                if(v==r) h=(60 * (g-b))/(v-getMin(b,g,r));
                else if(v==g) h=120 + (60 * (b-r))/(v-getMin(b,g,r));
                else if(v==b) h=240 + (60 * (r-g))/(v-getMin(b,g,r));
            }
            if(h<0) h=h+360;

            // hapus komen untuk normalisasi

            v = v;
            s= 255*s;
            h=h/2;

            newPixel.val[0]=h;
            newPixel.val[1]=s;
            newPixel.val[2]=v;

            imgHSV.at<Vec3b>(i,j)[0]=h;
            imgHSV.at<Vec3b>(i,j)[1]=s;
            imgHSV.at<Vec3b>(i,j)[2]=v;


        }
    }
    imshow("RGB", img);
    imshow("HSV tanpa library", imgHSV);

    cvtColor(img,imgHSV2,CV_BGR2HSV); // menggunakan library openCV
    imshow("HSV Dengan Library OpenCV", imgHSV2);
    cvWaitKey(0);

    return 0;
}